The invention relates to an arrangement for leading flexible elements, such as hoses, around a hose reel to a rock drill moving along a feed beam, in which arrangement the flexible elements are coupled at least at one point in their longitudinal direction immovably relative to the feed beam, led to travel towards the rear end of the feed beam, around a hose reel that revolves round a shaft essentially perpendicular relative to the feed beam and moves at one half the rate of the rock drill relative to the feed beam behind the rock drill in the same direction with respect to the rate of the rock drill, and further to the rock drill or a carriage thereof.
The invention further relates to a hose reel structure for leading flexible elements to a rock drill moving along a feed beam, the hose reel structure comprising a hose reel that revolves round a shaft and the hose reel comprising control means for each flexible element, such as a guide groove or the like for leading the flexible elements in a preset order around the hose reel.
Several different hoses have to be led to rock drills for them to operate. However, the hoses have to be kept straight and a certain tension maintained during drill movement. This is typically achieved by arranging the hoses so that they travel from the drill towards the rear portion of the feed beam around a hose reel in the rear portion, and further towards the front portion of the feed beam, and by coupling the movements of the drill and the hose reel so that the hose reel moves to the same direction as the drill, but at one half its rate, and thus half the distance that the drill moves. In known solutions all hoses travel around the same reel structure so that the hoses are on top of each other in the axial direction of the reel. Furthermore, in cylinder feeds a wire is used in the same way as hoses for turning the hose reel around to achieve movement, the hose reels in use being quite high. As a result, a hose reel typically extends significantly farther as the drill in the elevation of the feed beam and hence the upper portion of the hose reel is easily damaged especially when holes are drilled near the surface of a tunnel. In some known solutions a separate idler wheel is used for the wire coaxially with the actual hose reel, but even in this case they are arranged in succession in the axial direction of the hose reel thus forming a high structure. Such solutions are known e.g. from U.S. Pat. No. 3,500,941 and German Offenlegungsschrift 2,419,470.